1. Field of the Disclosure
The present application relates to the technical field of mineral separation equipment, and particularly to a vertical ring high gradient magnetic separator.
2. Discussion of the Background Art
One of the conventional main methods for wet separating weak magnetic minerals is to separate materials by using a vertical ring high gradient magnetic separator.
The vertical ring high gradient magnetic separator is a kind of device for wet separating weak magnetic minerals using a higher magnetic field generated by a cooled winding coil having a lower temperature. The separation principle of the vertical ring high gradient magnetic separator is as follows: the magnetic field generated by the winding coil passes through upper and lower magnetic yokes to form a magnetic circuit; a rotary ring mounted with a magnetic medium is provided in a space between the upper and lower magnetic yokes and the winding coil. A lower part of the rotary ring is immerged in ore slurry, and along with the rotation of the rotary ring, the magnetized medium absorbs magnetic mineral particles onto a surface of the magnetic medium.
After the rotary ring brings the magnetic medium immerged in the ore slurry to leave the ore slurry and rotates by a certain angle, pressure water provided at the top of the rotary ring flushes the magnetic mineral particles into a concentrate collection apparatus to achieve the separation of materials.
A higher magnetic field is required to realize the separation of the weak magnetic minerals and many associated minerals, and the magnetic field is mainly generated by the winding coil. From a technical perspective, when the winding coil has same parameters, such as the number of turns, wire diameter, material, current, voltage, the higher the temperature rise of the coil is, the greater the wire resistance is, and the greater the thermal decay of the magnetic field is, and also the insulation of the coil declines gradually.
At present, the cooling way of the vertical ring high gradient coil mainly includes an inner-cooling way and an external-cooling way.
The inner-cooling way uses a copper hollow conducting wire, and cooling water is introduced into the conducting wire to take away heat. Since the water contains some impurities, during a long-term using process, the cooling water is easy to form limescale to block the hole of the coil, thereby causing a high failure rate. In addition, the cooling water after being used drains away directly, which causes a serious waste of water resources, and there are also other disadvantages, such as high consumption of copper, high cost and complicated process.
In the external-cooling way, the coil is immerged in cooling oil, the cooling oil circulates outside the winding coil to dissipate heat by a cooling apparatus in the circulation circuit. The cooling effect of this cooling way mainly depends on two aspects: the capability of the cooling oil of taking away the heat of the winding coil timely, and the capability of the cooling apparatus of dissipating heat of the cooling oil. As for the first aspect, the existing formed winding coil generally forms an compact unity, and only the external of the winding coil can in contact with the cooling oil directly, therefore, the cooling oil can only take away the heat at the outer surface of the winding coil timely, and the heat generated inside the winding coil can only be transferred to the external of the winding coil first and then is transferred to the cooling oil. Due to the restriction of heat conduction efficiency, a lot of heat may accumulated inside the winding coil and can not be dissipated, thereby causing the rise of the overall temperature of the winding coil and reduction of the magnetic field strength.
Therefore, a technical problem to be solved by those skilled in the art is to improve the heat dissipation capability of the winding coil of the vertical ring high gradient magnetic separator in the coolant so as to ensure the winding coil maintaining a lower temperature during operation, thereby obtaining a higher magnetic field strength.